This proposal addresses the problems of growth deformities after epiphyseal plate (physeal) fracture, or subsequent to developmental deficiencies. Acquired growth deformity has been gaining considerable attention in the recent literature as a frequently underestimated and presently unsolved clinical problem. Premature complete or asymmetric closure of the growth plate occurs in 50% or more of childhood fractures of the distal femur. It leads to significant crippling problems in many of these unfortunate patients, with few satisfactory solutions. A new approach is suggested for treatment of the physeal injury. The technique of applying traction across the growth plate, which was originally utilized by Russian surgeons for "bloodless limb lengthening" will be evaluated for prophylactic and for correct treatment of skeletal growth arrest. This assessment begins with in vitro biomechanical studies of the mode in which epiphyseal plates fail when subjected to varying levels of axial traction. The method of applying traction a cross the plate to produce a growth response without fracture failure will then be evaluated. Both failure and sub-failure traction loads will be utilized to prevent and/or to correct epiphyseal growth arrest in an animal model. Various techniques and devices including spring-loaded and turnbuckle mechanisms will also be compared in the animal model, both with in vitro and in vivo applications. In addition to the indications and effectiveness of epiphyseal traction, its contraindications and complications will also be considered. Areas of concern include the adverse effects on subsequent epiphyseal growth and damage to the joint surface. Disruption of the epiphyseal collagen fiber architecture in particular may lead to early obliteration of the epiphyseal cartilage columns and will be analyzed in this proposal. Alterations in the circulation to the epiphysis and the physis must also be considered as a potential complication of the method. Arthritic changes in the articular surface adjacent to the growth center must also be carefully looked for after the epiphysis is manipulated. All these advantages and disadvantages, the biophysical effects of epiphyseal traction, are considered in this proposal. Such a careful, indepth analysis is important, and indeed imperative, before epiphyseal plate surgery, which has already been reported in some U.S. and European centers becomes widely disseminated in this country.